Lens flare is a generally undesirable feature of some images, which causes these images to appear foggy. This foggy appearance may occur when, for example, light incident on individual pixels in an image sensor is scattered before it reaches the sensor, spreading the light amongst all or many of the pixels in the image sensor. Lens flare has several known causes, among which may include oils, dirt, finger prints, lint, dust and/or other contaminants on the lens of the camera which includes the image sensor.
Lenses on conventional cellular telephone cameras do not have lens covers or, if they do, the lens covers are slid by a user's fingers to cover or uncover the lens. Due to the lack of lens cover or, alternatively, to the user sliding his or her fingers in the vicinity of the lens to cover and uncover the lens, cellular telephone camera lenses may easily become covered with contaminants (e.g., oils, finger prints, etc.). Also, when a user places the camera in his or her pocket, purse, or other container or leaves the camera out for an extended period of time, the lens may become covered with contaminants (e.g., dirt, lint, dust, etc.). While not as prevalent a problem for non-phone digital cameras, lenses on such cameras may become contaminated as well.
Because images produced by a camera appear foggy when its lens is contaminated, the user will likely notice that the camera is not producing quality images. The defects in the image produced by the imager through a contaminated lens are commonly called “lens flare.” Many users, however, will not know that the unsatisfactory images are caused by contaminants on the lens. Further, even if the user does know that such unsatisfactory images may be caused by contaminants on the lens, a user looking through the view finder (a different lens) or the preview screen (which is often too small to see the image clearly) may not notice that the lens is contaminated before he or she takes the picture. Accordingly, the user may attribute the poor quality of the images to the quality of his or her camera instead of taking appropriate steps to clean the lens.